A context-specific latent inhibition effect in a human conditioned suppression task

Abstract

Three studies used a computer video game preparation to demonstrate latent inhibition in adult humans. In all studies participants fired torpedoes at a target spaceship by clicking the mouse. Conditioned stimuli (CSs) were presented in the form of coloured “sensors” at the bottom of the screen. Conditioning was conducted by pairing a sensor with an attack from the target spaceship. Participants learned to suppress their rate of mouse clicking in preparation for an attack. In Experiment 1 a total of 10 preexposures to the sensor CS, prior to conditioning, retarded acquisition of suppression. In Experiment 2 the effect of preexposure was shown to be context specific. Experiment 3 showed little generalization of the preexposure effect from one sensor CS to another. Experiment 3 also showed that preexposure did not make the sensor CS inhibitory. Comparisons with conditioned suppression procedures with animals and negative-priming procedures are briefly discussed.

This work was made possible by Grant Number 1 R15 MH65249–01A1 awarded to the first author from the National Institutes of Health and a postdoctoral grant awarded to the second author from the Spanish Ministry of Education, Culture, and Sport (Programa de becas postdoctorales en España y en el extranjero, reference EX2002–0812). The authors are grateful to Geoffery Hall, Gonzalo de la Casa, and Juan Manuel Rosas for their comments on drafts of this manuscript. The program used in these studies can be obtained, free of charge, by contacting the first author.